Tissue will be collected from the operation theatre only after having obtained the patient´s consent and in strictest accordance with histopathological requirements, i.e. after assessment of resection margins. It might be necessary to retrieve the tissue from the pathologist after first pathological assessment is completed. Tissue will be placed in Tyrode´s solution, gassed with 95 % O2 and 5 % CO2, for functional and RT-PCR or Western blot experiments, or in OCT (optimal cutting temperature) compound, snap-frozen in liquid nitrogen, and stored in a -80°C freezer until cutting for immunohistochemical experiments.